Method of making disk wheels



Oct. 12, 1937. v E. A. NELSON METHOD OF MAKING DISK WHEELS 2 Sheets-Sheet 1 Filed March 25, 1955 INVENTOR. E2771! )7. Aka/ 507?.

Mm Wm Oct. 12, 1937. E. A. NELSON 2,095,343

METHOD OF MAKING DISK WHEELS Filed March 25, 19255 2 Shets-Sheet 2 INVENTOR. l l7. flelsarz ATTORNEY 15.

Patented Oct. 12, 1937 UNITED s'rrss eAT-ENToFncE METHOD OF MAKING DISK WHEELS Emil A. Nelson, st. Clair Shores, Mich. Application March 23, 1935, Serial No. 12,555

Claims.

This invention relates to an improved method for forming metal articles.

More particularly, the invention pertains to a method for forming improved steel disk wheels and/or blanks from which such wheels and other articles may be constructed.

One'of the main objects of the invention is to provide a method of this character by which.

reduced diameter and whichmay be so constructed and arranged as to maintain the thickness of the metal of such reduced portions equal to, less than, or greater than the initial thickness of the stock of the blank.

. A further object of the invention is to provide a method of this kind by which substantially the initial grain and flow line structure of the stock is preserved in the thin portions of the article formed thereby, and which is provided with a greater compactness in the structure of the metal of the thickened portions of such articles as compared with the corresponding initial characteristics of the stock.

A further object of the invention is'to provide of uniform thickness without requiring removal of any of the metal in the formation of the central hub passages with which wheels of this kind are conventionally provided; and to provide a method of this character by which the portion of the disk wheel, which in practice is securable to the wheel hub, may be brought to a greater thickness than the initial uniform thickness of ent invention, the same consists in certain novel features of construction and combination of parts to be hereinafter described with reference to the accompanying drawings, and then claimed, having the above and other objects in view.

All illustrative embodiment of the invention is shown in the accompanying drawings, in which: Fig. 1 is aside elevational view of a-tubular blank from which a pair of disk wheels may be formed by the improved apparatus and method.

Fig. 2 is an end elevational view of the tubular blank shown in Fig. 1.

Fig. 3 is a fragmentary, side elevational View, partly in section, of a preformed blank which is suitable for formation into a pair of disk wheel blanks by apparatus embodying the invention.

Fig. 4 is a side elevational view, partly in vertical section, of a wheel forming machine embodying the invention.

Fig. 5 is a top plan view showing a mandrel of the machine illustrated in Fig. 4, as viewed from the line 5-5 of the latter.

Fig. 6 is a transverse, sectional View, partly in end elevation, taken on the line 6-6 of Fig. 4

and showing the mandrels of the forming mato the positions thereof before commencement of their forming strokes. v

Fig. 7 is a view, similar to Fig. 6, but illustrating the positions in which themandrels are disposed at the completion of their stroke thereof. Fig. 8'is a diametrical, sectional view showing the condition of the stock after removal thereof from the forming machine. Fig. 9;is a diametrical, sectional View of one of a pair .of completed disk wheels which may be produced from one of the unitedwheel blanks illustrated in Fig. 8.

In the accompanying drawings a machine is shown which is particularly suitable for carrying out the present invention, and which forms the subject matter of my application for Letters Patent of the United States, for Improvements in apparatus for forming disk wheels or the like, filed December 11,1936 and serially numbered 115,330, the same constituting a division of the present application.

Referring to the drawings, the. forming machine shown in Figs. 4 to '7, inclusive, includes a base supporting structure, generally designated by the numeral it, and preferably comprising a suit ably cored casting which is centrally located with respect to a frame structure generally designated by the numeral II. The frame structure II includes upper and lower vertically aligned and longitudinally extending I beams I2 and I3, respectively, which are supported intermediate their ends by the base structure Ill and at their opposite end portions by pairs of vertical supports l4 andl5, respectively. Formed in the central chine in their extended positions corresponding structure ll and in each of which is shiftab-ly mounted an inner sleeve I 6. Formed on the inner end of each shiftable sleeve I6 is a radial flange IT.

A roller I8 having an elongated stem or hub portion I9 is rotatably carried by each sleeve I6 and disposed in facing relationship between the radial flanges II of the sleeves It. The hub portion IQ of each roller is supported by a pair of rolling contact bearing elements 29 disposed within the central passage of each sleeve I6, as illustrated in Figs. 6 and 7. The bearing members 2:! are seated in counterbores 2| formed in the opposite end portions of each sleeve I6 and they are soconstructed and arranged that one bearing member resists inward axial thrust of the hub portion I9 while the other bearing resists outward axial thrusts thereof, the outward axial thrust being applied on the innermost bearing by a nut 22 threaded on the inner end of each hub portion I9. The facing sides 23 of the rollers I8 are of frusto-conical contour and the peripheral portion of each roller is provided with an undercut continuous slot 24.

Shiftably mounted on the upper I beam I2 of the frame structure II is a mandrel 25 having a forming portion 32 which tapers in width and increases in depth from its right end, as viewed in 4, to its left end portion. The mandrel 25 is shiftably supported on the I beam I2 by spaced rollers .26 which are rotatably mounted on lugs 2'? attached to or formed integral with the mandrel. The rollers 26 extend between the flanges of the opposite sides of the I beam I2 and are disposed in rolling contact engagement with the lower opposite side flanges thereof so as to" support the mandrel 25 in suspended relation. Shiftably mounted on the lower I beam I3 is a mandrel 2i substantially'identical in shape to the mandrel 25. The forming portion 32' of the mandrel 521, however, tapers in width and increases in depth from its left end to its right end, as viewed in Fig. 4. r I

The mandrel 2'! is shiftably mounted on the I beam I3 byspaced pairs of rollers 28 which are rotatably mounted on lugs 29 formed integral with or fixed to the lower side 'of this mandrel. The rollers 23 extend between the flanges of the opposite sides of the I beam I3 and are disposed in rolling contact engagement with the lower flanges of the opposite sides thereof so as to support the mandrel 21 in upright position. Each of the mandrels 25 and 21 is held against outward movement from the axes of the rollers I8 by a pair of wheels 80 journaled on a shaft 3| carried by the base structure IIl'and disposed in vertical alignment with the axis of the roller I8, as illus trated in Figs. 4, 6 and. 7. The wheels 30 relieve the rollers 25 and 28 of the outward thrust exerted upon the mandrels 25 and 27 during the forming operation.

Each forming portion of the mandrels 25 and 21 varies in cross sectional shape from the contour shown in Fig. 6 at the wide end portion thereof to the contour shown in Fig. 7 at the smaller end portion. The forming portions 32 and 32' of the respective mandrels are constructed and arranged so as to extend between the frusto-conical facing sides of the rollers I8 to a successively greater depth during progressive movement of the mandrels from their starting positions illustrated in Fig. 4, to their respectively opposite limiting positions illustrated in section in Fig. '7. The forming'parts of the mandrels 25 and 2'! have side wall portions 33 which conform generally to the facing conical side portions of the rollers I8.

These portions of the side walls of the forming parts of the mandrels are relieved, as illustrated at 34 in Fig. '7, in order to reduce the areas of frictional contact between the inandrels and the work. This construction provides arrow-head shaped edge portions 35 at the adjacent edge portions of the mandrels which serve to perform the final forming operation of the machine.

Provided on the opposite longitudinal sides of each mandrel 25 and 2? are substantially vertical, converging cam surfaces 36 which converge from a maximum spaced relationship at the inner ends of the mandrels, as viewed in Fig. 4, to a minimum spaced relationship at the outer end portions thereof. These cam surfaces are adapted to predetermine the rate of feeding of the metal of the stock operated upon by the machine to the space between the facing frusto-conical sides of the rollers I 8 in a manner hereinafter set forth.

The mandrels 25 and 21 are, during operation of the machine, moved simultaneously in opposite directions from, their starting positions shown in Fig. 4 by hydraulic, pneumatic or combinations of hydraulic and pneumatic actuating means. In the form shown, each mandrel is provided with an actuating rod 31 which extends longitudinally of the supporting frame I I and which is threaded in an aperture of, or otherwise suitably attached to, the starting end portion of its associated mandrel. Provided on the outer end portions of the actuating rod 3? are pistons 38 which are slidably mounted in cylinders 39, each mandrel having its own associated piston and cylinder. The adjacent ends of the cylinder 39 are connected in parallel with a source of fluid medium under pressure, such, for example, as oil, by a conduit 40 which communicates intermediate its ends with a three-way valve 4|, having a fluid medium inlet 42 connected with a suitable source (not shown) of fluid pressure medium, and an exhaust outlet 43 leading to a suitable drain or return pipe (not shown). The outer ends of the cylinder 39 are connected in parallel with the valve 4i and fluid medium inlet 42 by a conduit 44. The valve 4| is adapted to be adjusted so as to supply the fluid medium to the conduit 40 and to bring the conduit 44 into communication with the exhaust outlet 43, for the purpose of forcing the pistons 48 outwardly with respect to each other and moving the mandrels 25 and 21 inwardly from their starting positions shown in Fig. 4. The valve 4I may be also set, as illustrated in Fig. 4, to bring the source of fluid pressure into communication with the conduit 44 and the exhaust outlet 43 into communication with the conduit 40 so as to supply fluid medium to the outer ends of the cylinders 39 and move the pistons 33 inwardly with respect to each other and to thereby return the mandrels to their starting positions.

During movement of the mandrel longitudinally of the frame structure II and transversely with respect to the axes of the rollers I8, the latter are moved inwardly toward each other by fluid pressure actuating mechanism illustrated in Fig. 6 and including a pair of cylinders 46 associated with each roller I8 respectively. Slidably mounted in each cylinder 46 is a piston 4'5 having a piston rod 48 threaded in an aperture 49 formed in the flange ll of the roller supporting sleeve I6. The flange ll of each sleeve I 6 is provided with spaced pairs of inwardly extending lugs 50 on which spaced rollers are rotatably mounted aboutyertical axes. Each roller, of each flange ii is disposed in rolling contact with one of the cam surfaces of corresponding sidesof the mandrels 25 and 2? respectively; When fluid pressure, such, for example, as oil under pressurejis portions of the cylinders 46 may be manually controlled by a valve 52 having a fluid medium outlet 53 connected by a conduit 55 with the inner end portions of all of the cylinders and having a fluid medium outlet 55 connected with the outer end portions of all of the cylinders by a conduit Thevalve 52 has a fluid medium inlet 51 connected with a suitable source (not shown) of fluid under pressure, and it is also provided with an exhaust outlet 58 which is connected with a drain or return pipe (not shown). When the valve is set in the position illustrated inFig. 6, the outlet 53 thereof communicates with the fluid pressure inlet 51 so as to supply fluid medium under pressure to the inner end portions of all of the cylinders, and the conduit 56 communicates with the exhaust outlet 58. This valve may be adjusted to bring the outlet 55 into communication with the inlet 51 so as to supply fluid medium under pressure to the outer end portions of all of the cylinders while permitting the inner end portions of the cylinder to communicate with the exhaust outlet 58. I

In operation, a piece of sheet metal, such as sheet steel, of substantially rectangular shape is brought to cylindrical form in any conventional manner and the edge portions of the stock are welded together, as illustrated at 5? in Fig. 2, so as to provide a sheet metal tubular blank 58. A sheet metal tubular blank 58 of the form shown in Figs. 1 and 2, may, if desired, be operated upon directly in the foregoing forming machine, but it is preferable to preform the blank to the contour shown in Fig. 3 in any conventional rolling process. The blank 59, as shown in Fig. 3, has a depressed intermediate portion of arcuate contour which is disposed between cylindrical rim or end portions 5i. The blank 59, or a blank of the type shown in Figs. 1 and 2 may be brought to a desired contour in a single operation of the foregoing machine so as to simultaneously provide a pair of joined disk wheel blanks of the character shown in Fig. 8. This may be accomplished by bringing the mandrels 25 and 27 to their starting positions illustrated in Fig. 4, and then placing a blank, for example, the blank 59 which has preferably been heated to a desired plasticity, on the lower mandrel 27 in the position illustrated in dotted lines in Fig. 4 andallowing the blank to roll into the space between the rollers I8 while the latter-are spread apart. The operator then adjusts the valve 52 to that position thereof which admits fluid under pressure to the outer end portions of all of the cyl-,

inders 46 so as to force the rollers 18 inwardly toward each other. During inward movement of the rollers l8, the cylindrical rim portions (SI of the blank 59 are engaged in the undercut slots 24 of the rollers l8, the relationship of the blank, mandrels and rollers at this stage of the process being illustrated in section 'in Fig. 6. The valve 52 is left in the foregoing adjusted position and the operator then adjusts the valve 45 so as to apply fluid pressure to the inner ends of the cylinders 39, thereby causing the upper mandrel 25 to be shifted to the right and the lower mandrel 2! to be shifted simultaneously to the left, as viewed in Fig. 4.

1 During these operating strokes of the mandrels 25 and El, the rollers 5| of thefeeding mechanism follow the converging cam surfaces 35 of the mandrels so as topermit progressively inward movement of the rollers toward each other in timed relation to the movement of the man drel. Thef cam surfaces 36 are so constructed and arranged with respect to the contour of the working parts 52 of the mandrels as to'propor tion the feeding of the metal of the blank with respect to the rate of depression of the intermediate portions thereof between the rollers. In the formation of steel disk wheels it ispreferable to feed the work at such a rate as to increase the thickness of that portion of the blank which is brought to the contourof the facing frus'toconical sides of the rollers l8. In some instances, however, it may be desirable to maintain the initial thickness of the metal of the blank in the finished product and in this event the cam surfaces 56 may be predetermined to accomplish this result. If desired, the cam surfaces may be so constructed and arranged as to permit a predetermined amount of stretching of the metal during depression thereof between the rollers so as to thereby reduce the thickness of the deformed portion of the blank. When the deformed portion of the blank is increased in thickness as compared to the initial thickness there of, a gradual variation in thickness, illustrated in Figs. 8 and 9, from the thickness of the stock at the outermost portions of the blank to a maximum thickness at the innermost deformed portions thereof, may be produced. After the working strokes of the mandrels have been completed and the normally outer ends of the mandrels 27 have passed each other at the inner positions of their strokes, the blank. is removed and the operator then adjusts the valve 52 to exhaust the fluid pressure from the outer end portions of all of the cylinders 46 and to admit fluid pressure to the inner. end portions of such cylinders. Thereafter, the valve M is so adjusted as to admit fluid pressure to the outer end portions of the cylinders 39 so as to retract the mandrels 2'! to their starting position, and to condition the machine for another operating cycle.

The formed blank which has been removed is substantially in the condition illustrated in Fig. 8 and is then severed along the line 52 so as to provide two steel disk wheel blanksfiwhch may be readily brought to the final shape'shown in Fig. 9, between suitable dies (not shown). The resulting 'disk wheel has a rim portion 53 which has been subjected to substantially no work during the forming operation and in which the grain structure and flow lines are substantially the same or correspond substantially with the grain and flow lines of the initial blank. The side portions 64, however, of the disk wheel shown in Fig. 9, is increased in thickness as compared to the thickness of the stock. This increase has been effected by crowding of the metal of the blank during the forming operation and, as a result, the grain structure is somewhat more compact than that of the initial blank and the flow lines of the metal of the side portion 64 of the wheel are not elongated as compared to the flow lines of the initial blank.

During the foregoing forming process, the intermediate portion of the blank 59 is forced inwardly sufiiciently to provide a disk wheel side forming portion having a length of'cross section substantially equal to that desired in the finished product. The central opening 65 with which disk wheels of this character are conve'ntionally provided is formed by discontinuing the inward depression of the intermediate portion of the blank at a predetermined depth and substantially no metal is cut away or'otherwise wasted. In this manner, a material saving is effected for all of the metal which the original flat, rectangular sheet of stock contained, is present in the final product.

Although but one specific embodiment of the invention has been illustrated and described in detail, it will be apparent to those skilled in the art that various modifications may be made without departing from the scope of. the appended claims.

I claim:

1. The method of simultaneously forming a pair of disk wheel blanks each having a wheel rim providing part and a Wheel side providing part which comprises forming a rectangular piece of sheet metal into tubular stock, supporting the end portions of said stock against inward distortion, forming between said end portions a peripheral groove having inwardly converging side walls and having a radial depth corresponding to the length of radial section desired in said wheel side providing part, moving the end portions of said stock toward each other, during forming of said groove, sufiiciently to maintain the thickness of. said wheel side providing part at least equal to the initial thickness of said stock, and severing said stock at the junction of said converging walls to provide separate wheel blanks each having a central opening in its wheel side providing part without wasting any of said stock.

2. The method of forming a disk wheel blank having a wheel rim providing part and a wheel side providing part which comprises forming a piece of sheet metal into tubular stock, supporting the end portions of said stock against radially inward distortion, forming between said end portions a peripheral groove having a depth corresponding to the length of radial section desired in said wheel side providing'part, moving the end portions of said stock toward each other, during forming of. said groove, sufiiciently to maintain the thickness of said wheel side providing part at least equal to the initial thickness of said stock, and severing said stock adjacent the innermost portion of said groove to provide'a wheel blank having a central opening in its wheel side providing part.

3. The method of forming a disk wheel blank having a wheel rim providing part and a wheel side providing part which comprises forming a piece of sheet metal into tubular stock, supporting the end portions of said stock against radially inward distortion, forming between said end portions a peripheral groove having a depth corresponding to the length of radial section desired in said wheel side providing part, applying, during forming of. said groove, sufiicient axially inwardly directed pressure on the opposite end portions of said stock to maintain the thickness or" said wheel side providing part at a predetermined value, and'severing said stock adjacent the innermost portion of said groove to provide a wheel blank having a central opening in its Wheel side providing part.

4. The method of simultaneously forming a pair of disk wheel blanks, each having a wheel rim providing part and a wheel side providing part which comprises supporting the end portions of a piece of tubular stock against inward distortion, forming betweensaid end portions a peripheral groove'having inwardly converging side walls and having a radial depth corresponding to the length of radial section desired in said wheel side providing part, moving the end portions of said stock toward each other, during forming of said groove, suiiiciently to maintain the thickness of said wheel side providing part at least equal to the initial thickness of said stock, and severing said stock at the junction of said converging walls to provide separate wheel blanks each having a central opening in its wheel side providing part without wasting any of said stock.

5. The method of forming a disk wheel blank having a wheel rim providing part and a wheel side providing part which comprises supporting the end portions of a piece of tubular stock against radially inward distortion, forming between said end portions a peripheral groove having a depth corresponding to the length of radial section desired in said wheel side providing part, applying, during forming of said groove, sufiicient axially inwardly directed pressure on the opposite end portions of said stock to maintain the thickness of said wheel side providing part at a predetermined value, and severing said stock adjacent the innermost portion of said groove to provide a wheel blank having a central opening in its wheel side providing part.

EMIL A. NELSON. 

